CKEditor - Real-time collaborative future-ready rich text editor
Moom - Move your mouse over the green zoom button in any window, and Moom's mouse control overlay will appear (as seen in the above animation).
Summernote - Summernote is a JavaScript library that helps users create WYSIWYG editors online.
Hammerspoon - This is a tool for powerful automation of OS X.
Froala Editor - Froala Editor is a WYSIWYG HTML editor that enables rich text editing capabilities for the applications.
Spectacle App - Move and resize windows with ease.